Synchronizing device for wire-activated mechanisms

ABSTRACT

Apparatus for synchronizing the operation of a pair of wire-operated mechanisms such as a carburetor and a lubricating oil pump. In order to take up block or looseness which may exist, the actuated wires from the mechanisms are connected to a rocker beam which is part of a slider. An actuating wire is connected to the slider. Lock means is unlocked and enables the rocker beam to equalize tension in the two wires until a sufficient force is exerted by the actuating wire, whereupon the lock means locks the beam and the adjusted actuating wires operate the mechanisms in synchronism.

The present invention relates to synchronizing apparatus wherein a pair of wire-actuated mechanisms are simultaneously actuated by a single actuating wire.

In known motorcycles utilizing, for example, two stroke cycle engines, two Bowden-type actuated wires are connected at their first ends to an actuating Bowden-type wire, which in turn is operatively connected to the throttle grip of the motor cycle. The actuated Bowden wires are respectively connected at their other ends to a throttle valve of a carburetor, and to a pulley for controlling the plunger stroke of a lubricating oil pump, respectively, so that the throttle-valve opening and the pump plunger stroke may be controlled in synchronization with each other.

In such an arrangement of wires, however, certain amounts of play are involved in the movement of the actuated Bowden wires, due to looseness of connection and/or slack of the wires. The amounts of play of both of said actuated Bowden wires are not always equal to each other. Consequently, if the slack or play are not suitably compensated or adjusted after the assembling of the Bowden wires, such a disorder of synchronization may occur that the throttle valve remains closed because the play of the Bowden wire for the throttle valve is not completely taken up, whereas the play of the bowden wire for the lubricating oil pump has been taken up and this wire brings the plunger-stroke adjusting pulley into action, resulting in an excessive supply or shortage of the lubricating oil.

For this reason, conventionally the adjustment of the Bowden wires must be made taking the difference of amounts of play of the two Bowden wires into account. this is highly complicated and troublesome.

At the same time, even if the adjustment of the Bowden wires has been made correctly at the time of the forwarding or shipping of the motor cycles, the amount of play of the actuating Bowden wires will in time differ from each other, due to different amounts of wear of the connecting portions and different amounts of elongation of wires caused in the long use, resulting in a deterioration of the synchronized operation of the associated mechanisms.

It is therefore an object of the invention to overcome the above described problem of the prior art by providing an improved synchronizing device which adjusts and ensures correct synchronous operation, despite elongation of wires which may take place as a result of long use.

Apparatus according to this invention includes a slider in a case. The actuating wire is connected to the slider, and the actuated wires are connected to a rocking beam which forms part of the slider. Lock means releases the rocking beam to rock and equalize tension in the two actuating wires until a sufficient tension is applied by the actuator wire. Then the lock means locks and the adjusted actuating wires move in synchronism.

According to a preferred but optional feature of this invention, the beam includes an arcutate structure which bears inter-engaging surfaces adapted to be engaged by other such surfaces for locking purposes.

The above and other objects, as well as advantageous features of the invention will become clear from the following description of preferred embodiments taken in conjunction with the accompanying drawings.

FIG. 1 is a top view of the presently-preferred embodiment of the invention, with portions removed, cutaway, and shown in cross-section.

FIG. 2 is a cross-section taken at line 2--2 in FIG. 1;

FIG. 3 is an exploded view in oblique view, of the device of FIG. 1;

FIG. 4 shows the device of FIG. 1 in a linkage system in one condition wherein the locking means is released;

FIG. 5 is similar to FIG. 4, wherein the locking means is locked; and

FIG. 6 is a plan view of another embodiment of the invention.

Referring first to FIGS. 1 to 5 showing a first embodiment of the invention, the device of the invention has a case 1 with a closure member 2. The case 1 axially slidably receives a slider 3, having a slider body 3a both ends of which have guiding projections 4,5 formed unitarily therewith. The shoulder portions of each guiding projection 4, 5 constitute guiding steps 6. A rocker beam 7 is provided at both of its ends with guiding notches or recesses 8,9 adapted to slidably engage the guiding steps 6 of guiding projections 4, 5. Guide 7 is thereby guided for free sliding movement.

A rocker beam generally designated at numeral 10 has an upper rotary flange 11 and a lower retaining flange 12 of a larger diameter than the upper rotary flange 11. A shaft 13 or post projects from the center of the lower surface of the retaining flange 12 unitarily with the latter. The above mentioned rotary flange 11 is rotatably received in a hole 14 formed almost at the center of guide 7, while shaft 13 is slidably and rotatably received in an elongated bore 15 formed almost at the center of the slider.

Retainer flange 12 is received in a gap formed between the guide 7 and the slider 3. Consequently, beam 10 is allowed to rotate around a center of rotation (the center of hole 14). Also, it slidingly moves along with the rotor guide 7 in the axial direction.

Locking teeth 16 (sometimes called "inter-engageable surface") are formed on the outer periphery of the retaining flange 12 of the beam 10, over almost half of the entire circumference of the same. Cooperating locking teeth 17 (also sometimes called "inter-engageable surfaces") are formed on a side surface of a guiding projection 4 on the slider so as to confront teeth 16. The arrangement is such that the retaining teeth 16, 17 are brought into and out of engagement with each other, as the beam 10 is slided relatively to the rest of the slider.

An abutting projection 18 )sometimes called a "skirt") is formed at one end of guide 7. It extends downwardly from the latter, so as to oppose one end surface of the guiding projection 5, with a suitable space left therebetween. Guiding projection 5 has a spring hole 19 which opens in one end surface thereof and accommodates a compression (bias) spring 20.

Spring 20 acts on the abutting projection 18, so as to bias guide 7 and the beam 10 rightward as viewed in FIGS. 1 and 3, i.e. in the direction of disengagement of the teeth 16 and 17.

A retainer 21 ("retainer means") having a head portion 22 of a diameter larger than the breadth of the guiding recess 9 of the red guide 7, and a leg portion 23, is adapted to hold the slider together. The head portion 22 is slidably received by a recess 24 formed in guide 7, while the leg portion 23 is received by a bore 25 formed in guiding projection 5. The aforementioned spring hole 19 opens at its other end in the inner surface of the bore 25. A pin 26 abutting the other side of the spring 20 is biased by the latter so as to project into the bore 25.

The end portion of the leg portion 23 of the retainer 21 is cut obliquely, so as to form a tapered surface 27. A bore 28 is formed to open in the surface of an intermediate portion of the leg portion 23, at opposite side of the latter to the tapered surface 27.

The retainer 21 is inserted into the bore 25, with its tapered surface 27 directed toward the pin 26. As the leg portion is pressed deeper into the bore 25, the tapered surface 27 depresses the pin 26. Then, as the leg portion 23 is rotated by a half turn, the pin 26 is again projected and received by the bore 28, so that the retainer is anchored. It will be seen that this anchoring of the retainer 21 can be made without using any specific tools.

Slider 3 has a wire-end retaining bore 29 formed in the top surface of guiding projection 5 at the one end of the latter. The wire-end retaining bore 29 is adapted to receive and firmly retain the wire end 31 of actuating wires 34, 35.

The force of spring 20 is so selected as to be smaller than the sume of the forces of reset springs of the operated mechanisms and, preferably, larger than the force of one of these reset springs.

Caps 39 pass the ends of wires 30, 34, 35. This can be formed unitarily with case 1.

Slits 40 for passing the wires 30, 34, 35 are formed through the upper part of wire caps 39 and through the associated portions of the top face of the case body 1.

One end of the closure member 2 is elongated to form a flange 41 from the lower face of which retaining projections 42, 42 project into the slits 40 thereby to hold the wires therein.

In the first embodiment of the invention having the above described construction, the actuating Bowden wire 30 is connected to a manipulating mechanism such as a throttle grip A as illustrated in FIG. 4, while the actuted Bowden wires 34, 35 are connected to the mechanisms to be manipulated, e.g. the throttle valve C of the caburetor C and to the plunger-stroke adjusting pulley E of the lubricating oil pump D. Both of these mechanisms have a resetting spring which opposes acturation of the mechanism.

When the throttle grip A is held at its starting position, i.e. when the actuating and actuated Bowden wires 30, 34, 35 are released from the tension, the teeth 16 of the retaining flange 12 beam 10 disengage from the teeth 17 of the slider 3, due to the biasing force of the spring 20, so that the beam is free to rotate (rock).

Then, as the throttle grip A is rotated to cause a tension in actuating wire 30, the slider 3 is pulled by wire 30. This pulling force is transferred to the beam 10 through the spring 20 and the guide 7, so that the beam 10 is moved along with the remainder of slider 3, thereby to pull the actuated Bowden wires 34, 35. The resistance or tensions caused in these wires are small enough, while the displacements of these wires are within the ranges of plays of respective wires, so that the tension across the connecting portion of actuating and actuated wires 30 and 34, 35, i.e. the force which acts to move the beam guide 7 relative to slider body 3a. is sufficiently small that no substantial compression of the spring 20 takes place. Therefore, the teeth 16 and the teeth 17 are out of engagement with each other, so as to allow the free rotation of the rotor 10.

Supposing here that the play amounts of the actuated wires 34, 35 are different, e.g. that the actuated Bowden wire 34 for the carburetor B has become slightly enlongated to make the play larger. Then at first the play of the actuated Bowden wire 35 for the lubricating oil pump D will be taken up exhausted as the throttle grip A is further rotated. Consequently, a resisting pulling force or tension is caused in the wire 35, corresponding to the force of the reset spring G. As the actuating Bowden wire 30 is further pulled to cause the displacement of rotor 10, only the actuated wire 34 for the carburetor B is pulled, while the wire 35 for the lubricating pump D is not pulled any more, partly because the resistance force in the wire 34 for the carburetor B is still small as the displacement of the same has not exceeded the play length yet, and partly because the rotor 10 is held for free rotation, through a rotation of the rotor 10 as illustrated in FIG. 4.

Provided that the distances of the actuated Bowden wires 34, 35 from the center of rotation of the beam are equal to each other, the increment of the compression force of the spring 20, from the time before the operation of the throttle grip to the time at which only the carburetor is wire 34 is pulled, is two times as large as the resistance of the actuating Bowden 34 for the carburetor B.

The resistance of the wire 34 is being pulled is extremely small when the displacement of the same is within the range of the play, so that no substantial compression of the spring 20 takes place, so as to allow the free rotation of the beam even in this state.

Then, as the throttle grip is further rotated, the play of the actuated Bowden wires is exhausted, and therefore, a resistance force corresponding to the force of the reset spring F is generated in the actuated Bowden wire 34 for the carburetor.

Consequently, a further pulling of the actuating Bowden wire 30 increases the force which acts to move the slider body 3a and the rotor 10 relative to each other, so that these two members are moved relative toward and away from each other, compressing the spring 20, thereby to bring the retaining teeth 16, 17 into engagement with each other. In this state, the beam can no longer rotate so that the two actuated Bowden wires 34,35 are pulled translationally without any lost motion, thereby to operate the throttle valve C of the carburetor B and the plunger-stroke control pulley E of the lubricating oil pump D synchronization.

This synchronization effect is achieved more remarkably in the returning rotation of the throttle grip A, to the time immediately before the returning of the latter to the starting position. Namely, the force applied to the spring 20 in this returning stroke is smaller that the same force exerted in the throttle-opening rotation of the throttle-grip by an amount twice as large as the frictional force between the inner wires 34, 35 and the outer wire 38, so that the retaining teeth 16, 17 remain in engagement to prevent rotation of the beam until sufficient force is relieved, thereby to ensure an effective synchronization effect during release of the tension.

The described embodiment is not exclusive, and the invention can be carried out in different forms.

For instance, referring to FIG. 6, which shows a second embodiment of the invention, rocking beam 10' may be rotatably attached to a movable slide body 43 to which lock member 3' is rotatably secured. According to the arrangement of the second embodiment, lock member 3' is rotated overcoming the force of a "clothespin" bias spring 20', when a force larger than a predetermined force acts across the connection between the actuating Bowden wire 30 connected to lock member 3' and the actuated Bowden wires 34, 35' secured to beam 10', so that the teeth 17' formed on the movable member 3' are brought into engagement with the teeth 16' formed on the beam 10', thereby to lock the beam 10' against rotation.

Thus, this second embodiment is materially identical to the first embodiment, excepting that the lock member 3' is adapted to rotate relatively to the rotor 10'.

The minor parts such as the mechanism for locking the rotor can be embodied in other forms than the described one. All that is required is to mount a beam rotatably relatively to the remainder of the slider adapted to be moved by the actuating Bowden wire, and to allow rotation of the rotor only when the force acting across the connecton between the actuating and actuated Bowden wires is beneath a predetermined force.

As has been described, according to the invention, there is provided a synchronizing device comprising a slider or a movable member adapted to be moved by the actuating Bowden wire, and rocking beam forming part of the slider, the beam being adapted to be locked against rotation when the plays in actuated Bowden wires, which are connected to two diametrically opposing portions of the rotor, have been taken up to cause predetermined tensions in these actuated Bowden wires.

Consequently, the effective movements of the actuated Bowden wires are simultaneously and translationally commenced to operate the mechanisms in synchronization.

It is therefore unnecessary to make an adjustment of the actuated wires for the synchronized operation of the mechanisms, taking the difference of the play amounts into account.

At the same time, the difference of the amounts of plays attributable to the elongation and/or wear of the connecting portions of the actuated Bowden wires, as a result of a long use, is automatically corrected to ensure an accurately synchronized operation of the objective mechanisms.

In the described embodiment, the synchronizing device of the invention is used for maintaining the synchronized operation of a carburetor and a lubrication oil pump. However, the device can be used for maintaining synchronized operation of other combination of mechanisms, e.g. for maintaining a synchronized operation of a pair of carburetors.

The radial distance between the axis of rotation of the rotor 10 and the connecting ends of respective manipulated-side Bowden wires 34, 35 may be selected in accordance with the resistance force exerted by respective mechanisms to be operated.

At the same time, it is to be noted here that the present invention can be applied not only to the described Bowden wire arrangement consisting of an inner wire and a sheath, but also to ordinary wire arrangement consisting only of the inner wires.

The term "rocking beam" is used to connote an arrangement wherein two wires are connected to a rotatable object, one on each side of the center of rotation. The "beam" can, of course, be round, and in the FIG. 1 device it is.

The term "slider" includes all parts within the case in FIG. 1, and all parts illustrated in FIG. 6, except the wires.

The term "lock member" or "lock means" or "locking means" in FIG. 1, means teeth 16, 17, and in FIG. 6 means member 3' and the teeth carried by it and by the beam. The lock members are "tension-actuated", because it requires sufficient tension on the wires to cause the lock means to lock the beam.

This invention is not to be limited by the embodiments shown in the drawings and described in the description, which are given by way of example and not of limitation, but only in accordance with the scope of the appended claims. 

I claim:
 1. Apparatus for synchronizing the operation of a pair of mechanisms, each of which is actuated by a respective actuated wire, and each of which includes a respective re-setting spring which opposes actuation of the respective mechanism, said apparatus comprising:a slider having an axis of movement, said slider being adapted for connection to an actuating wire whose movement moves the slider and the actuated wires, said slider comprising a slide body, a rocking beam rockably mounted to said slider body, said beam having a center of rocking rotation, and being adapted to be connected to an end of both of said actuated wires, one on each side of said center, tension-actuated locking means adapted to lock said rocking beam against rotation when sufficient tension is exerted in the wires, and resilient bias means tending to unlock said locking means, thereby to permit rocking movement of said rocking beam, whereby upon pulling on the actuating wire with less than said sufficient tension, the rocking beam is released to rock to equalize tension in both of said actuated wires, thereby drawing the slider to adjust said actuated wires and to remove slack from both of them, and upon application of said sufficient tension, the locking means locks to hold said adjustment, and further pulling on said actuating wire pulls both of said actuated wires in synchronism to actuate the said mechanisms in synchronism.
 2. Apparatus according to claim 1 in which the slider comprises a first body part and a second body part, said parts being connected to each another and axially shiftable relative to one another, said actuating wire being connectible to said first body part, and the rocking beam being mounted to said second body part, said locking means comprising interengageable surfaces on said beam and on said first body, and said bias means biasing the body parts relative to one another so as to move said surface away from said interengagement, a sufficient pull on said wires overcoming the resistance of said bias means and causing said surfaces to interengage and lock the beam against rocking.
 3. Apparatus according to claim 2 in which said surfaces comprise teeth on an actuate surface carried by the rocking beam, and teeth on the first body.
 4. Apparatus according to claim 3 in which said beam is incorporated into an element having a substantially circular bearing surface, and said second body includes a matching circular bearing surface.
 5. Apparatus according to claim 4 in which said beam has a post and said first body part has a axial slot receiving said post.
 6. Apparatus according to claim 2 in which said first body part has a cavity to receive an enlargement on the end of the actuating wire, and in which retainer means holds said engagement in the cavity.
 7. Apparatus according to claim 6 in which the second body part has a depending skirt, and the said bias means is carried by said first body part in axial alignment with said skirt to bias the body parts relative to one another.
 8. Apparatus according to claim 7 in which said surfaces comprise teeth on an actuate surface carried by the rocking beam, and teeth on the first body.
 9. Apparatus according to claim 8 in which said beam is incorporated into an element having a substantially circular bearing surface, and said second body includes a matching circular bearing surface.
 10. Apparatus according to claim 1 in which the slider comprises a body to which the beam is rotatably mounted, and in which the locking means includes a lever pivotally mounted to the body having a first arm attachable to the actuating wire, and a second arm adapted to be drawn against the rockable beam to prevent its rotation, said bias means biasing the second arm away from the beam.
 11. Apparatus according to claim 10 in which the lever is L-shaped.
 12. Apparatus according to claim 10 in which the locking means includes inter-engageable surfaces on said second arm and on said beam.
 13. Apparatus according to claim 12 in which said bias means is a clothespin-type spring.
 14. Apparatus according to claim 13 in which the lever is L-Shaped.
 15. Apparatus according to claim 1 in which said slider is enclosed in a case, which supports the slider for axial movement.
 16. Apparatus according to claim 2 in which said slider is enclosed in a case, which supports the slider for axial movement.
 17. Apparatus according to claim 3 in which said slider is enclosed in a case, which supports the slider for axial movement. 